My problem is exactly as described above. One minute everything is completely fine, I export to pdf, everything is perfect. The next minute, right in the middle of working, I notice pages are starting to become blank. Sometimes it's random objects, sometimes full pages. The links show up in the links panel and on the layers panel, but you can no longer see them or select them on the pages. If you export to pdf, they are not there. If you try to select them, you only see a teeny tiny square in the middle of the page, you can't resize it or zoom into it.
There have been times when I have been able to close without saving, reopen, and all is fine. But most times, it's irreversible. If I close the file even WITHOUT saving, the next time I open it, the items are still missing. I can attach the file if there is any way to do that on here. I have used InDesign for years, and I am positive I am not doing anything to cause this. One minute it's fine, the next it's messed up. It happens a lot of times after an export to PDF, but sometimes just at random times.